Hair cutting appliances, particularly electric hair cutting appliances, are generally known and may include trimmers, clippers and shavers. Electric hair cutting appliances may also be referred to as electrically powered hair cutting appliances. Electric hair cutting appliances may be powered by electric supply mains and/or by energy storages, such as batteries, for instance. Electric hair cutting appliances are generally used to trim (human) body hair, in particular facial hair and head hair to allow a person to have a well-groomed appearance. Frequently, electric hair cutting appliances are used for cutting animal hair.
U.S. Pat. No. 6,968,623 B2 discloses a hair trimmer comprising a body, a cutting head including a blade set, an adjustable comb, wherein the comb is movable with respect to the blade set, an electric motor for driving the blade set to effect a cutting action, and an actuator assembly that is capable of moving the comb with respect to the blade set between a fully retracted position and a fully extended position, the actuator assembly comprising a comb carriage, a comb button connected to the comb carriage, wherein the comb button is actuatable to adjust the position of the comb relative to the blade set, and a lock button movable with respect to the comb button, wherein the lock button selectively prevents and permits movement of the comb button relative to the body. Consequently, manual adjustment of the length of the comb is enabled.
EP 2 500 153 A2 discloses a hair grooming appliance comprising a housing; at least one hair grooming device carried by the housing and adapted to facilitate grooming of hair, said at least one hair grooming device comprising a blade selectively movable with respect to the housing and adapted to cut hair; an adjustable comb assembly including a comb selectively movable relative to the blade, and a comb-driving assembly operatively coupled to the comb; a control circuit in the housing and in communication with said at least one hair grooming device; and a touchscreen for receiving at least one input from a user, the touchscreen being configured to send at least one command signal to the control circuit in response to receiving said at least one input from the user, wherein the control circuit is configured to control an operation of the adjustable comb assembly, and wherein the operation of the adjustable comb assembly includes the comb-driving assembly moving the comb relative to the blade to a selected hair cut-length setting of the hair grooming appliance.
US 2008/163495 A1 discloses a hair clipper with a motorized cutting guide which comprises a motor connected by a shaft to the cutting guide. The cutting guide is driven by a program available via a microprocessor suggesting various options to the user. The user can operate the cutting guide in a manual mode and an automatic mode. The user can operate the cutting guide by pressing virtual buttons at a touchscreen.
A comb for a hair cutting appliance, particularly a spacing comb, generally may be arranged as an attachable comb or an integrally formed comb. A spacing comb generally spaces a blade set of the hair cutting appliance from the skin when the appliance is moved in a moving direction with respect to the skin during operation. Consequently, the spacing comb may enable to cut hair to a desired length, i.e. to a desired length of remaining hair at the skin.
Conventional hair cutting appliances may be fitted with a set of attachment combs, each of which associated with a distinct hair length. Consequently, a user of the appliance basically needs to replace an attachment comb by another one to alter the hair cutting length. Furthermore, manually adjustable comb attachments are known, as disclosed in U.S. Pat. No. 6,968,623 B2. Furthermore, also powered adjustment combs have been presented in recent years, as for instance disclosed in EP 2 500 153 A2. Typically, powered adjustment combs comprise a movable comb portion that is movable with respect to a blade set of the hair cutting appliance, wherein the movable comb portion is coupled to an actuator, particularly to an electromotor and/or an electric powertrain.
However, operating a motorized adjustment comb frequently has proven to be afflicted with several drawbacks. It is often cumbersome for the user to operate the adjustable spacing comb in a precise and accurate manner since typically rather conventional control elements are provided, for instance push buttons, control levers etc. Typically, these control elements provide a predefined user input sensitivity. In other words, a single user input action may cause a defined response of the motor such that the adjustable spacing comb is displaced by a defined distance or step. Basically the same applies to conventional touchscreens, as shown in EP 2 500 153 A2.
Consequently, coarsely positioning the adjustable spacing comb in the provided adjustment range (which may include covering considerably long distances in the adjustment range) may be experienced as time-consuming. Furthermore, fine adjustment of the adjustable spacing comb may be difficult since conventional control elements typically require considerably large minimum increments of the adjustment motion, as indicated above. Consequently, operating a motorized adjustable spacing comb by means of conventional control elements may be regarded as a trade-off between adjustment speed and adjustment precision.
Due to the above-mentioned lack of operating and adjusting efficiency of conventional adjustable spacing comb arrangements, operating the hair cutting appliance may be further complicated. It would be therefore advantageous to simplify the act of adjusting the spacing comb. It would be further advantageous to provide an adjustable spacing comb and an adjustment drive therefor that may be operated by the user in a time-efficient and highly accurate manner.
There is thus still room for improvement in length adjustment mechanisms.